耳鸣掩蔽对耳鸣患者脑干听觉诱发电位波幅的影响

背景:研究发现耳鸣患者常伴有脑干听觉诱发电位波幅大Ⅲ小Ⅴ波的变化,耳鸣掩蔽是耳鸣治疗中的一种方法,在耳鸣掩蔽的治疗过程中耳鸣患者脑干听觉诱发电位将会如何变化?目的:观察耳鸣患者的脑干听觉诱发电位变化特点,以及耳鸣掩蔽后脑干听觉诱发电位变化规律。设计:病例-对照及自身前后对照。单位:吉林大学第一医院耳鼻咽喉--头颈外科。对象:持续性耳鸣组:63例(68耳),为1999-03/2001-10吉林大学第一医院门诊收治;对照组:听力正常的青年人(20～23岁)10例(20耳)。所有受试者自愿接受检测及治疗。方法:耳鸣患者首先进行脑干听觉诱发电位检查(采用额部乳突部引导方法记录),然后进行耳鸣检查及耳鸣掩蔽试验(掩蔽5min),随后立刻做脑干听觉诱发电位检查,并与对照组进行对比观察。主要观察指标:①耳鸣患者脑干听觉诱发电位的特点。②耳鸣掩蔽后对脑干听觉诱发电位波幅的影响,分为后效抑制试验阳性和阴性2组进行分析。结果:83例全部进入结果分析。①听力正常青年人的脑干听觉诱发电位波幅为小Ⅲ波大Ⅴ波,而63例(68耳)中有22耳(31.2%)脑干听觉诱发电位为大Ⅲ波小Ⅴ波,其中17耳后效抑制试验阳性,5耳阴性。②后效抑制试验阳性17耳经耳鸣掩蔽治疗后10耳由大Ⅲ波小Ⅴ波转为小Ⅲ波大Ⅴ波,3耳Ⅲ波幅度减小;阴性5耳经耳鸣掩蔽治疗后有2耳转为小Ⅲ波大Ⅴ波,其余3耳无改变。结论:耳鸣掩蔽能使耳鸣患者异常的脑干听觉诱发电位波幅恢复至正常,此结果有望作为后效抑制阳性判定的客观指标。

Effect of tinnitus masking on auditory brainstem response wave amplitude in patients with tinnitus

BACKGROUND: Research shows that the auditory brainstem response (ABR) wave amplitude of tinnitus patients often act as big Ⅲ small Ⅴ.Tinnitus masking is a therapy of tinnitus, then how dose the ABR change in the process of tinnitus masking?OBJECTIVE: To observe the changing characteristics of ABR in patients with tinnitus as well as the changing rules of ABR after tinnitus masking.DESIGN: Case-control and self-control.SETTING: Department of Otorhinolaryngology, First Hospital of Jilin University.PARTICIPANTS: Continuous tinnitus group: 63 cases (68 ears) were selected from the Clinic of First Hospital of Jilin University from March 1999to October 2001. Control group: 10 cases (20 ears) of normal hearing youth (20-23 years old). All subjects received the examination and treatment voluntarily.METHODS: The ABR was firstly detected in tinnitus patients (foreheadmastoid conducting method was adopted), and examination of tinnitus as well as tinnitus masking test (masking for 5 minutes) were respectively conducted, immediately after that, the ABR was detected to do control-observation with the control group.MAIN OUTCOME MEASURES: ①The characteristics of ABR in patients with tinnitus. ②Effects of tinnitus masking on the amplitude wave of ABR, which was divided into positive group in residual inhibition test and negative group in residual inhibition test for analyzing.RESULTS: A total of 83 subjects were involved in the analysis of results.①The amplitude wave of ABR in youth of normal hearing were small Ⅲ big Ⅴ, whereas that in 22 ears (32.4％) out of 63 subjects (68 ears) were big Ⅲ smallⅤ, in which 17 ears were of patients positive residual inhibition test, and 5 were of negative.②After tinnitus masking therapy, 10 ears out of 17 ears of patients positive in residual inhibition test turned from big Ⅲ small Ⅴ to small Ⅲ big Ⅴ, and the wave amplitude of Ⅲ wasre duced in 3 ears, while the ABR in 2 ears out of 5 ears of negative patients turned to small Ⅲ bigⅤ, and there were no changes in other 3 ears.CONCLUSION: Tinnitus masking therapy can convert the abnormal ABR wave amplitude in patients with tinnitus to normal, which will be taken as the objective index in judging whether it is positive in residual inhibition test.